Identification of direct transcriptional target genes of ExoS/ChvI two-component signaling in Sinorhizobium meliloti

We performed transcriptional profiling with chvI gain-of-function (EC220) and reduced-function (EC69) strains. The chvI gain-of-function strain that we used contains a dominant gain-of-function chvI allele in addition to wild-type chvI. We identified genes that, relative to their expression level in the wild type, are both upregulated in the chvI gain-of-function strain and downregulated in the reduced-function strain or vice versa. Gene expression profiling of Sinorhizobium meliloti Rm1021-derived strains, with wild type or mutant chvI alleles, using custom Affymetrix GeneChips